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1.
PLoS One ; 14(12): e0226278, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31881027

RESUMO

Wastewater treatment plant effluents are important point sources of micropollutants. To assess how the discharge of treated wastewater affects the ecotoxicity of small to medium-sized streams we collected water samples up- and downstream of 24 wastewater treatment plants across the Swiss Plateau and the Jura regions of Switzerland. We investigated estrogenicity, inhibition of algal photosynthetic activity (photosystem II, PSII) and growth, and acetylcholinesterase (AChE) inhibition. At four sites, we measured feeding activity of amphipods (Gammarus fossarum) in situ as well as water flea (Ceriodaphnia dubia) reproduction in water samples. Ecotoxicological endpoints were compared with results from analyses of general water quality parameters as well as a target screening of a wide range of organic micropollutants with a focus on pesticides and pharmaceuticals using liquid chromatography high-resolution tandem mass spectrometry. Measured ecotoxicological effects in stream water varied substantially among sites: 17ß-estradiol equivalent concentrations (EEQbio, indicating the degree of estrogenicity) were relatively low and ranged from 0.04 to 0.85 ng/L, never exceeding a proposed effect-based trigger (EBT) value of 0.88 ng/L. Diuron equivalent (DEQbio) concentrations (indicating the degree of photosystem II inhibition in algae) ranged from 2.4 to 1576 ng/L and exceeded the EBT value (70 ng/L) in one third of the rivers studied, sometimes even upstream of the WWTP. Parathion equivalent (PtEQbio) concentrations (indicating the degree of AChE inhibition) reached relatively high values (37 to 1278 ng/L) mostly exceeding the corresponding EBT (196 ng/L PtEQbio). Decreased feeding activity by amphipods or decreased water flea reproduction downstream compared to the upstream site was observed at one of four investigated sites only. Results of the combined algae assay (PSII inhibition) correlated best with results of chemical analysis for PSII inhibiting herbicides. Estrogenicity was partly and AChE inhibition strongly underestimated based on measured steroidal estrogens respectively organophosphate and carbamate insecticides. An impact of dissolved organic carbon on results of the AChE inhibition assay was obvious. For this assay more work is required to further explore the missing correlation of bioassay data with chemical analytical data. Overall, the discharge of WWTP effluent led to increased estrogenicity, PSII and AChE inhibition downstream, irrespective of upstream land use.


Assuntos
Anfípodes/fisiologia , Cladóceros/fisiologia , Complexo de Proteína do Fotossistema II/efeitos dos fármacos , Águas Residuárias/análise , Águas Residuárias/toxicidade , Acetilcolinesterase/metabolismo , Proteínas de Algas/efeitos dos fármacos , Anfípodes/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Cromatografia Líquida , Cladóceros/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Rios/química , Suíça , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Purificação da Água
2.
Ecotoxicol Environ Saf ; 186: 109743, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31593827

RESUMO

Nanoparticles (NPs) production is increasing worldwide. These products are likely to end up in aquatic environments. However, few studies evaluated the chronic toxicity of iron-based NPs (Fe-NPs) to cladocerans and their potential ecotoxicological hazards. In this study we aimed to investigate the effects of iron oxide nanoparticles (Fe3O4-NPs) to Ceriodaphnia silvestrii Daday, 1902, assessing acute (48 h) and chronic toxicity (up to 14 d). Besides traditional endpoints (immobility and lethality), we also evaluated physiological responses (respiration rates) in a 48 h-exposure. No immobility was observed (EC50 > 100 mg L-1) after 48 h, whereas respiration rates at the highest concentration were 400% of that in control, indicating that this endpoint was more sensitive during acute toxicity. In chronic assays, Fe3O4-NPs affected body length (8.24% growth inhibition in 7 d-exposure) and number of eggs (7-d IC10: 3.53, IC20: 6.69 mg Fe L-1) and neonates (7-d IC10: 1.25, IC20: 3.75 mg Fe L-1). Based on species sensitivity distribution (SSD), C. silvestrii was a sensitive organism, suggesting Fe-NPs as a possible threat for this species. Our results also indicate that the NPs caused a physical barrier, impairing food absorption, since we observed NPs agglomerations into cladocerans' gut. We demonstrate that Fe3O4-NPs affects C. silvestrii metabolism and reproduction and our results support the use of sublethal endpoints to assess environmental safety. The release of these NPs into freshwater environments should be carefully evaluated, since disturbances on cladoceran population dynamics could cause strong impacts on the entire food web structure and ultimately on ecosystem functioning.


Assuntos
Cladóceros/efeitos dos fármacos , Nanopartículas de Magnetita/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cladóceros/fisiologia , Ecossistema , Reprodução/efeitos dos fármacos , Testes de Toxicidade
3.
Artigo em Inglês | MEDLINE | ID: mdl-31561619

RESUMO

Applications of nanotechnologies in different sectors and everyday items are very promising and their popularity continues to grow. The number of products containing nanoparticles makes environmental exposure to nanoparticles inevitable. The current understanding of the relationships between nanoparticles and the environment is inadequate despite the fast growth of nanotechnologies. The aim of the study was to investigate the influence of copper and gold nanoparticles on Daphnia pulex survival. Our study included 48-hour acute toxicity tests and determination of median lethal concentration values (LC50s) for Cu-NPs and Au-NPs. For nano-copper, 24 h LC50 was assumed > 1 mg/L, and 48 h LC50 = 0.5117 mg/L. For nano-gold the LC50 value after 24 h was 0.4027 mg/L, and after 48 h 0.1007 mg/L. The toxicity of nano -gold solutions was thus found to be higher than that of nano-copper. The addition of Cu-NPs at 0.0625 mg/L and 0.125 mg/L caused an increased multiplication of daphnia, while Au-NPs at 1 mg/L was an inhibitor of reproduction.


Assuntos
Cladóceros/efeitos dos fármacos , Cobre/química , Ouro/química , Nanopartículas Metálicas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Daphnia , Dose Letal Mediana , Nanopartículas Metálicas/química , Testes de Toxicidade Aguda , Poluentes Químicos da Água/química
4.
Ecotoxicol Environ Saf ; 185: 109694, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31562998

RESUMO

Bisphenol S (BPS) and 4-hydroxyphenyl 4-isoprooxyphenylsulfone (BPSIP) have been used as substitutes for bisphenol A (BPA) owing to increased regulation of BPA in plastics. In this study, long-term toxicity tests of BPS and BPSIP were performed using Daphnia magna and Moina macrocopa. The predicted no-effect concentration (PNEC) of BPA, BPS, and BPSIP were derived by the assessment factor (AF) method and the species sensitivity distribution (SSD) method. An ecological risk assessment was performed based on the measured environmental concentrations of BPA in surface water worldwide and the derived PNECs. The chronic NOEC of D. magna was 2.5 mg/L for BPS and 0.5 mg/L for BPSIP, and that of M. macrocopa was 0.03 mg/L for BPS and 0.1 mg/L for BPSIP. The PNECAF was generally one order of magnitude less than the PNECSSD, and the PNEC of BPS was 10 times lower than that of BPA. The hazard quotients of BPA and BPS exceeded 1, indicating that concentrations in ambient water conditions could pose a potential risk to aquatic organisms. Since the use of alternative compounds is increasing, further monitoring data of the water environment and chronic toxicity in various aquatic organisms appears to be necessary.


Assuntos
Compostos Benzidrílicos/toxicidade , Cladóceros/efeitos dos fármacos , Água Doce/química , Fenóis/toxicidade , Sulfonas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ecologia , Medição de Risco , Testes de Toxicidade
5.
Artigo em Inglês | MEDLINE | ID: mdl-31390928

RESUMO

Cladocerans are constantly exposed to humic substances in nature, yet the effects of these substances on their survival and reproduction are not well known. Here, the effects of humic substances (20 and 40 mg L-1) (HS) on the life history variables of three common cladocerans, Ceriodaphnia dubia, Moina macrocopa, and Daphnia pulex were evaluated. The results showed that the effect of humic substances on the tested cladocerans is species-specific, affecting either survival, reproduction or both. For M. macrocopa, exposed to HS at a concentration of 40 mg L-1, the average lifespan and the life expectancy at birth were significantly reduced as compared to controls, but for C. dubia and D. pulex these parameters were increased. Gross reproductive rate was unaffected by the HS level for both D. pulex and M. macrocopa, but it was significantly higher for C. dubia. When compared to the corresponding controls, for HS-exposed cladocerans, the rate of population increase was significantly reduced in case of D. pulex while it was stimulated for both C. dubia and M. macrocopa. It appears that humic substances had a slightly stronger influence on survivorship than on reproduction of the tested cladocerans.


Assuntos
Cladóceros/efeitos dos fármacos , Substâncias Húmicas/efeitos adversos , Reprodução/efeitos dos fármacos , Animais , Cladóceros/fisiologia , Daphnia/efeitos dos fármacos , Demografia , Feminino , Substâncias Húmicas/análise , Masculino , Especificidade da Espécie
6.
Ecotoxicology ; 28(8): 890-902, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31392637

RESUMO

Aquatic pollution caused by dyes has increased together with the growth of activities using colorants such as the textile, leather, food, and agrochemicals industries. Because most popular azo dyes are synthesized from benzidine, a carcinogenic compound, a threat to aquatic biota could be expected. The use of single species for toxicity assessment provides limited data, so a battery of test organisms, including representatives of different trophic levels such as algae, zooplankters, and fish, could undoubtedly provide more information. Therefore, our study was aimed at evaluating the toxic effect of the azo dye Direct blue 15 (DB15) on a battery of bioassays using a primary producer (Pseudokirchneriella subcapitata), a primary consumer (Ceriodaphnia dubia), and a secondary consumer (Danio rerio). P. subcapitata was more sensitive to DB15 (IC50 = 15.99 mg L-1) than C. dubia (LC50: 450 mg L-1). In the algae exposed to DB15, chlorophyll-a and -b were significantly increased, and carotenoids were reduced. The concentrations of protein, carbohydrates, and lipids per cell in P. subcapitata exposed to all DB15 concentrations were significantly higher than that measured in control. At 25 mg L-1 of DB15, survival, total progeny, and the number of released clutches were significantly decreased, and the start of reproduction was delayed in C. dubia. DB15 did not induce lethal or sublethal effects in D. rerio embryos at any of the tested concentrations from 24 to 72 h post-fertilization (hpf), but from 96 to 144 hpf, the larvae exposed to 100 and 500 mg L-1 developed yolk sac edema, curved tail, and skeletal deformations. After 144 hpf, DB15 produced a significant increase in embryos without a heartbeat, as the concentration of dye raised. The textile-used, azo dye DB15, caused toxic effects of different magnitude on microalgae, cladocerans, and zebrafish embryos; for this reason, the discharge of this colorant into waterbodies should be regulated to prevent environmental impacts.


Assuntos
Compostos Azo/toxicidade , Clorofíceas/efeitos dos fármacos , Cladóceros/efeitos dos fármacos , Corantes/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Animais , Embrião não Mamífero/efeitos dos fármacos , Microalgas/efeitos dos fármacos
7.
Ecotoxicol Environ Saf ; 179: 310-317, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31030948

RESUMO

Bisphenol A (BPA) is a representative endocrine disrupting chemical (EDC) that has estrogenic effects in aquatic animals. In recent years, due to the continuing usage of BPA, its analogues have been developed as alternative substances to replace its use. The molting process is a pivotal point in the development and reproduction of crustaceans. However, studies of the effects of EDCs on molting in crustaceans at the molecular level are scarce. In the present study, we examined the acute toxicity of BPA and its analogues bisphenol F (BPF) and S (BPS) to the brackish water flea Diaphanosoma celebensis. We further identified four ecdysteroid pathway - related genes (cyp314a1, EcRA, EcRB, and USP) in D. celebensis, and investigated the transcriptional modulation of these genes during molting and after exposure to BPA and its analogues for 48 h. Sequencing and phylogenetic analyses revealed that these four genes are highly conserved among arthropods and may be involved in development and reproduction in the adult stage. The mRNA expression patterns of cyp314a1, EcRA and USP were matched with the molting cycle, suggesting that these genes play a role in the molting process in the adult stage in cladocerans. Following relative real-time polymerase chain reaction (RT-PCR) analyses, BPA and its analogues were found to modulate the expression of each of these four genes differently, indicating that these compounds can disrupt the normal endocrine system function of D. celebensis. This study improves our understanding of the molecular mode of action of BPA and its analogues in D. celebensis.


Assuntos
Compostos Benzidrílicos/toxicidade , Cladóceros/efeitos dos fármacos , Ecdisona/genética , Disruptores Endócrinos/toxicidade , Fenóis/toxicidade , Águas Salinas/química , Poluentes Químicos da Água/toxicidade , Animais , Compostos Benzidrílicos/química , Cladóceros/genética , Cladóceros/metabolismo , Ecdisona/metabolismo , Fenóis/química , Filogenia , Testes de Toxicidade Aguda , Transcrição Genética/efeitos dos fármacos
8.
Environ Pollut ; 249: 638-646, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30933761

RESUMO

Microplastics (<5 mm) are distributed ubiquitously in natural environments. The majority of microplastics in aquatic environments are shown to have rough surfaces due to various weathering processes (secondary microplastics; SMP), while laboratory studies predominantly utilise pristine microplastics (primary microplastics; PMP). Here we present the results from a study comparing the chronic effects of pristine PMP and artificially weathered SMP to three different Cladoceran species (Daphnia magna, Daphnia pulex, Ceriodaphnia dubia). We assessed the impact of PMP and SMP on reproductive output using various measured parameters, including time of first brood, size of first brood, size of first three broods, cumulative number of neonates, total number of broods and terminal length of test animals. Our results show that reproductive output of all species declined in a dose-dependent manner. The No Observed Effect Concentration (NOEC) was less than the lowest tested concentration (102 p/mL) for at least one measured endpoint for all species and both PMP and SMP. Further, it was inferred that species sensitivity varied inversely with body size for most endpoints, resulting in C. dubia being the most sensitive species; and D. magna being the least sensitive species under study. In addition, PMP appeared to have greater toxic potential as compared to SMP. This study is the first to directly compare the chronic toxicity of both pristine and weathered microplastic particles on three freshwater toxicological model organisms. Our results indicate that sensitivity in reproduction and growth to microplastics may differ between species and type of microplastic exposed; highlighting the importance of using multiple species and structural types of particles.


Assuntos
Cladóceros/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Nanopartículas/toxicidade , Plásticos/toxicidade , Reprodução/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais
9.
Environ Sci Pollut Res Int ; 26(12): 11743-11755, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30815811

RESUMO

Global consumption of synthetic dyes is roughly 7 × 105 tons per year, of which the textile industry expends about two-thirds. Consumption of synthetic dyes produces large volumes of wastewater discharged into aquatic ecosystems. Colored effluents produce toxic effects in the hydrobionts, reduce light penetration, and alter the photosynthetic activity, causing oxygen depletion, among other effects. Some dyes, such as Congo red (CR), are elaborated with benzidine, a known carcinogenic compound. Information regarding dye toxicity in aquatic ecosystems is scarce; therefore, our study was aimed at evaluating the toxicity of CR on a battery of bioassays: the microalga Pseudokirchneriella subcapitata, the cladocerans Daphnia magna and Ceriodaphnia rigaudi, and the zebrafish Danio rerio. P. subcapitata was the most sensitive species to CR (IC50, 3.11 mg L-1); in exposed individuals, population growth was inhibited, but photosynthetic pigments and macromolecule concentrations were stimulated. D. magna was tolerant to high dye concentrations, the determined LC50 (322.9 mg L-1) is not an environmentally relevant value, but for C. rigaudi, LC50 was significantly lower (62.92 mg L-1). In zebrafish embryos, exposure to CR produced yolk sac edema, skeletal deformities, and stopped larvae hatching; lack of heart beating was the only observed lethal effect. CR affected organisms of different trophic levels diversely. Particularly, the effects observed in microalgae confirm the vulnerability of primary producers to dye-polluted wastewaters, because dyes produced toxic effects and interfered with photosynthesis. Different cladoceran species displayed different acute effects; thus, species sensitivity must also be considered when toxicity of dyes is assessed. Inhibition of fish larvae hatching is a significant effect not previously reported that warns about the toxicity of dyes in fish population dynamics. Synthetic azo colorants should be considered as emerging pollutants because they are discharged into the aquatic environment and are not currently included in the environmental regulation of several countries.


Assuntos
Vermelho Congo/toxicidade , Testes de Toxicidade/métodos , Poluentes Químicos da Água/toxicidade , Animais , Cladóceros/efeitos dos fármacos , Corantes/toxicidade , Daphnia/efeitos dos fármacos , Embrião não Mamífero , Cadeia Alimentar , Larva/efeitos dos fármacos , Dose Letal Mediana , Microalgas , Indústria Têxtil , Águas Residuárias , Peixe-Zebra/embriologia
10.
Environ Sci Pollut Res Int ; 26(12): 11998-12013, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30827021

RESUMO

In the current study, the effect of different types of titanium dioxide (TiO2) nanoparticles (NPs) (rutile, anatase, and mixture) was analyzed on Ceriodaphnia dubia in the presence of algae under distinct irradiation conditions such as visible and UV-A. The toxicity experiments were performed in sterile freshwater to mimic the chemical composition of the freshwater system. In addition, the oxidative stress biomarkers such as MDA, catalase, and GSH were analyzed to elucidate the stress induced by the NPs on daphnids. Individually, both rutile and anatase NPs induced similar mortality under both visible and UV-A irradiations at all the test concentrations except 600 and 1200 µM where rutile induced higher mortality under UV-A. Upon visible irradiation, the binary mixture exhibited a synergistic effect at their lower concentration and an additive effect at higher concentrations. In contrast, UV-A irradiation demonstrated the additive effect of mixture except for 1200 µM which elucidated antagonistic effect. Mathematical model confirmed the effects of the binary mixture. The surface interaction between the individual NPs in the form of aggregation played a pivotal role in the induction of specific effects exhibited by the binary mixture. Oxidative stress biomarkers were highly increased upon NPs exposure especially under visible irradiation. These observations elucidated that the irradiation and crystallinity effect of TiO2 NPs were noted only on certain biomarkers and not on the mortality.


Assuntos
Cladóceros/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/química , Animais , Água Doce , Luz , Nanopartículas/química , Nanopartículas/toxicidade , Titânio/análise , Raios Ultravioleta , Poluentes Químicos da Água/toxicidade
11.
Environ Sci Pollut Res Int ; 26(13): 12881-12893, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30887454

RESUMO

Camorim is a small, eutrophic reservoir in Rio de Janeiro, Brazil, with a phytoplankton community dominated most of the year by the filamentous diatom Aulacoseira spp. and the toxic cyanobacterium Cylindrospermopsis raciborskii. As filamentous species can be a poor food for grazers, we hypothesize that phytoplankton from this reservoir would constrain cladoceran fitness due to nutritional limitation and/or toxicity when animals fed mixtures of cultured green algae and natural seston. Clones of different cladoceran species were exposed either to seston from Camorim reservoir sampled in different seasons or to a C. raciborskii strain (CYLCAM-2) isolated from the reservoir. In short-term assays, cladocerans were exposed to either 100% seston or mixtures of 50% seston added to green algae (200 µg C L-1), and their survivorship and somatic growth were measured for 4 days. In life table assays, neonates were exposed to the same seston treatments over 14 days and age at first reproduction, survivorship, fecundity, total offspring, and the intrinsic rate of natural increase (r) were assessed. In general, seston negatively affected cladoceran survivorship and fitness (r), but this response was seasonally and species specific. Stronger effects of CYLCAM-2 than those caused by seston on survivorship, somatic growth, and r were found for all cladoceran species, especially when the proportion of CYLCAM-2 was higher than 50% in relation to green algae in a fixed total food concentration. Our results suggest that both nutritional (C/P and morphology) and toxicity factors can act to impair cladoceran fitness and help explain the absence of cladocerans in Camorim reservoir.


Assuntos
Cladóceros/efeitos dos fármacos , Cianobactérias/química , Daphnia/efeitos dos fármacos , Fitoplâncton/química , Animais , Bioensaio , Brasil , Clorófitas , Cylindrospermopsis , Daphnia/química , Alimentos
12.
Environ Toxicol Pharmacol ; 68: 4-12, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30849701

RESUMO

In the field of nanoecotoxicology, very few reports have focused on biochemical changes in non-target organisms after nanoexposure. A less explored aquatic non-target crustacean, Moina macrocopa, was used in the present study to analyze toxicity effects of gold nanoparticles (AuNPs), an emerging nanomaterial. AuNPs was fabricated using tannic acid and were 29 ± 2 nm in size. The 48 h LC50 value of AuNPs was 14 ± 0.14 mg/L against M. macrocopa. The sub-lethal exposure of M. macrocopa juveniles to AuNPs (1.47 and 2.95 mg/L) decreased the activities of acetyl cholinesterase and digestive enzymes (trypsin and amylase). A concentration dependant increase in the activities of antioxidant enzymes such as catalase, superoxide dismutase and glutathione S-transferase suggested the generation of oxidative stress in M. macrocopa after AuNPs exposure. Changes in enzyme activity can be utilized as biomarker(s) for early detection of nanoparticle contamination in aquatic habitat. AuNPs accumulation in gut of M. macrocopa increased the metal bio burden (11 mg/L) and exhibited inhibitory action on digestive enzymes. Complete depuration of AuNPs was not observed after transferring nano-exposed M. macrocopa to normal medium without AuNPs. AuNPs tended to adhere on external body parts such as setae, carapace of M. macrocopa which interfered with swimming activity and also changed the behavioral pattern. AuNPs underwent agglomeration in the medium used for maintenance of M. macrocopa. As nanomaterials are emerging pollutants in aquatic systems, the present work highlights the hazardous effect of AuNPs and development of enzymatic biomarkers to curtail it at community level.


Assuntos
Cladóceros/efeitos dos fármacos , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Amilases/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Catalase/metabolismo , Cladóceros/fisiologia , Glutationa Transferase/metabolismo , Frequência Cardíaca/efeitos dos fármacos , Dose Letal Mediana , Superóxido Dismutase/metabolismo , Testes de Toxicidade/métodos , Tripsina/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-30789049

RESUMO

Ecotoxicological effects of the antiepileptic drug carbamazepine (CBZ) were investigated in one primary producer (Desmodesmus subspicatus) and seven invertebrate species (Daphnia magna, Daphnia pulex, Ceriodaphnia dubia, Gammarus fossarum, Potamopyrgus antipodarum, Lumbriculus variegatus and Chironomus riparius) using OECD and US EPA guidelines for chronic toxicity testing. The present data set was used to conduct a hazard assessment for CBZ including confirmatory data. While most of our results were in accordance with previous studies, published effect data for C. dubia and D. pulex could not be confirmed, even though they have previously been considered to be the most sensitive invertebrate species to CBZ exposure. The non-biting midge, C. riparius, was the most sensitive test organism in the present study. From an EC10 of 406 µg/L and a no observed effect concentration (NOEC) of 400 µg/L, a predicted no effect concentration (PNEC) of 8 µg/L was calculated. With regard to realistic predicted and measured environmental concentrations, the environmental risk can be considered as low for CBZ when the assessment is based on laboratory-based effect data. To conduct a refined and more realistic assessment, this study provides foundational data for two future, higher tier studies: one multiple-stressor experiment and one mesocosm study.


Assuntos
Anticonvulsivantes/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Carbamazepina/toxicidade , Poluentes Químicos da Água/toxicidade , Anfípodes/efeitos dos fármacos , Animais , Anticonvulsivantes/análise , Carbamazepina/análise , Chironomidae/efeitos dos fármacos , Cladóceros/efeitos dos fármacos , Daphnia/efeitos dos fármacos , Ecotoxicologia , Gastrópodes/efeitos dos fármacos , Nível de Efeito Adverso não Observado , Oligoquetos/efeitos dos fármacos , Especificidade da Espécie , Testes de Toxicidade Crônica , Poluentes Químicos da Água/análise
14.
Environ Toxicol Chem ; 38(3): 511-523, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30776146

RESUMO

We compared 2 statistical hypothesis-test approaches (no-observed-effect concentration [NOEC] and test of significant toxicity [TST]) to determine the influence of laboratory test performance on the false-positive error rate using the US Environmental Protection Agency's Ceriodaphnia dubia reproduction whole-effluent toxicity (WET) test endpoint. Simulation and power calculations were used to determine error rates based on observed control coefficients of variation (CV) for 8 laboratories over a range of effect levels. Average C. dubia control reproduction among laboratories was 20 to 40 offspring per female, and the 75th percentile CV was 0.10 to 0.31, reflecting a range in laboratory performance. The 2 approaches behave similarly for CVs of 0.2 to 0.3. At effects <10%, as CV decreases, TST is less likely to declare toxicity and NOEC is more likely to do so. Laboratory performance affects whether a sample is declared toxic and influences the probability of false-positive (and -negative) error rates using either approach. At the 75th percentile control CV observed for each laboratory, 4 laboratories would achieve approximately a 5% false-positive rate using 13 or fewer replicates for this test method. For the remaining 4 laboratories, more replicates would be needed to achieve a 5% false-positive rate. The present analyses demonstrate how false-positive rates are influenced by laboratory performance and WET test design. Environ Toxicol Chem 2019;38:511-523. Published 2019 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.


Assuntos
Testes de Toxicidade/métodos , Animais , Cladóceros/efeitos dos fármacos , Cladóceros/fisiologia , Interpretação Estatística de Dados , Feminino , Reprodução/efeitos dos fármacos , Estados Unidos , United States Environmental Protection Agency , Poluentes Químicos da Água/toxicidade
15.
Artigo em Inglês | MEDLINE | ID: mdl-30688169

RESUMO

Although chydorids are the most diverse cladocerans in the world, there is still little information available related to their biology and even less with respect to their susceptibility to toxicants. Therefore, this work aimed to implement protocols with Alona guttata for acute, chronic, and sublethal toxicity tests, using the environmental concern toxicants deltamethrin (DM) and lead (Pb2+), which are commonly used due to agriculture and vector control or for the automotive industry, respectively. Once the results of LC50 (0.1160 ± 0.0107 µg/L for DM and 1.5797 ± 0.1605 mg/L for Pb2+) were obtained, sublethal concentrations (0.01 to 0.2 LC50) were used for the evaluation of biomarkers and chronic toxicity. Concentrations as low as 0.01 LC50 reduced Alona's survival and fecundity, negatively affecting demographic parameters, and decreased the energy reserves. A significant correlation was found between the natural rate of population increase and the caloric content, which demonstrates the suitability of these biomarkers as endpoints of early warning that allow inferring alterations at higher biological levels. Subsequently, this work could constitute the first report on the evaluation of the energy budget in a non-daphnid species, its alterations due to exposure to toxic substances and the correlation with demographic responses.


Assuntos
Cladóceros/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Substâncias Perigosas/toxicidade , Chumbo/toxicidade , Nitrilos/toxicidade , Piretrinas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Cladóceros/metabolismo , Relação Dose-Resposta a Droga , Fertilidade/efeitos dos fármacos , Dose Letal Mediana , Testes de Toxicidade
16.
Arch Environ Contam Toxicol ; 76(1): 1-16, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30178132

RESUMO

The effect of sublethal concentrations of heavy metals on cladoceran growth and reproduction is a cornerstone of modern ecotoxicology. However, the literature contains assays across numerous concentrations, on numerous species and genotypes, and conditions are far from consistent. We undertook a systematic review of the sublethal effects of copper and cadmium concentrations on Cladocera spp. life history (reproduction, maturation age, and somatic growth rate). Using meta-analysis, we tested the hypothesis that the effects of increasing Cu and Cd concentrations on traits may vary by species. We also evaluated where possible whether the effect of metal concentrations on traits vary by water hardness, exposure duration, or whether the metals were delivered in aqueous solution or via food. We surveyed > 200 papers, resulting in a set of 32 experimental studies representing 446 trials where the results were presented compared with Daphnia magna-the most commonly assayed species. We found qualitatively similar effects of Cu and Cd on life history traits that included reduction in reproduction and somatic growth rate and delay of maturation. Cladocera species showed marked variations in their susceptibility to metals, and D. magna was found to be the least sensitive species to sublethal changes in reproduction. The effects were largely consistent for aqueous vs. dietary food. Water hardness, where data were available, had no detectable effect. Available data indicate that exposure duration had no effect on the toxicity of Cu but did for D. magna reproductive response to Cd. Our study highlights the importance of including species identity when considering toxicological testing and regulation development.


Assuntos
Envelhecimento/efeitos dos fármacos , Cádmio/toxicidade , Cladóceros/efeitos dos fármacos , Cobre/toxicidade , Traços de História de Vida , Poluentes Químicos da Água/toxicidade , Animais , Cladóceros/crescimento & desenvolvimento , Daphnia/efeitos dos fármacos , Daphnia/crescimento & desenvolvimento , Reprodução/efeitos dos fármacos , Especificidade da Espécie
17.
Bull Environ Contam Toxicol ; 102(3): 335-340, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30353307

RESUMO

The research aimed to determine critical concentrations of heavy metals at which survival of resting eggs of the cladoceran Moina macrocopa is negatively affected. Resting eggs' viability was not affected over a 30-days exposure towards copper, cadmium, zinc or nickel at concentrations up to 60-70 g/L. When resting eggs were exposed to sediment contaminated with heavy metals for 8 months, the hatching success was affected at 30 g copper/kg. Thus, resting eggs of Cladocera can tolerate heavy metals at concentrations that far exceed lethal concentrations of heavy metals to active life stage and exceed low or moderate levels of environmental pollution. Follow up investigation of life table parameters of hatchlings from resting eggs exposed to heavy metals demonstrated that neither lifespan nor fecundity of hatchlings differ from control animals. These results demonstrate that zooplankton may rapidly recover from resting egg bank once aquatic habitat becomes unpolluted.


Assuntos
Cladóceros/efeitos dos fármacos , Metais Pesados/toxicidade , Óvulo/efeitos dos fármacos , Animais , Cádmio/toxicidade , Cladóceros/crescimento & desenvolvimento , Cobre/toxicidade , Exposição Ambiental , Níquel/toxicidade , Óvulo/crescimento & desenvolvimento , Zinco/toxicidade
18.
Environ Toxicol Chem ; 38(1): 177-189, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30447090

RESUMO

The chronic toxicity of ammonia to tropical freshwater species is understudied, and thus data on temperate species have been used to derive water quality guideline values for tropical regions. Such practices may lead to underprotective guideline values due to differences in toxicities observed between tropical and temperate species. In addition, the presence of ammonia in low-ionic-strength waters may also result in higher toxicity, and studies on this factor are limited. The present study assessed the toxicity of ammonia to 6 tropical freshwater species in low-ionic-strength waters. Because ammonia toxicity varies depending on the pH and temperature, test water pH concentrations were maintained at approximately pH 6.0 ± 0.3 at temperatures between 27.5 and 30 °C. Low-effect chronic inhibition concentrations were derived for the following species: Chlorella sp. 66 mg L-1 ; Lemna aequinoctialis 22 mg L-1 ; Hydra viridissima 1.8 mg L-1 ; Moinodaphnia macleayi 27 mg L-1 ; Amerianna cumingi 17 mg L-1 ; and Mogurnda mogurnda 5.4 mg L-1 total ammonia nitrogen. Two of the species tested (a cnidarian and a fish species) were among the most sensitive reported anywhere within their taxonomic group. Chronic ammonia datasets representing toxicity estimates for temperate and tropical species were plotted and compared using species sensitivity distributions. The results indicate that the differences in chronic toxicity observed between tropical and temperate species were likely due to the low ionic strength of the waters to which tropical species were exposed, rather than any inherent physiological differences between species from tropical and temperate regions. This finding suggests that tropical waters of low ionic strength may be at a higher risk from ammonia compared with other freshwater ecosystems. Environ Toxicol Chem 2019;38:177-189. © 2018 Commonwealth of Australia. Published by Wiley Periodicals, Inc. on behalf of SETAC.


Assuntos
Amônia/toxicidade , Água Doce/química , Testes de Toxicidade Crônica , Clima Tropical , Animais , Araceae/efeitos dos fármacos , Austrália , Chlorella/efeitos dos fármacos , Cladóceros/efeitos dos fármacos , Hydra/efeitos dos fármacos , Perciformes , Controle de Qualidade , Especificidade da Espécie , Poluentes Químicos da Água , Qualidade da Água
19.
Environ Sci Pollut Res Int ; 26(2): 1435-1444, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30426375

RESUMO

Tunisia water resources are limited. The country currently has 29 large dams, more than 1000 hill lakes, and 220 small dams which are essential for economic and social development given their contribution to irrigation, drinking water consumption, flooding protection, production of electrical energy, groundwater recharge, and industrial uses. Given the scarcity of these resources, it is crucial to be able to ensure the quality of freshwater environments, particularly those intended for human consumption. In this study, we meant to assess the health status of various freshwater ecosystems in different regions of Tunisia (north and center west) in order to detect genotoxic components in sediments and their potential effect on zooplankton (cladocerans). Sediment and cladoceran species were collected from dams, ponds, and temporary rivers in Tunisia. For each collection site, micronucleus (MN) assay was performed, in triplicates, using a pool of ten specimens of the same cladoceran species. MN occurrence in cladocerans varied from one site to another and MN frequencies varied between 0.67 and 22‰, suggesting the presence of genotoxic substances in certain sites. Sediment genotoxicity and mutagenicity were assessed using the SOS Chromotest and the Ames test. Sediment results showed that genotoxicity varies from one site to another displaying a quantitative and a qualitative variation of pollutant among the sites. These results suggest an urgent need for continuous monitoring of freshwater environments in Tunisia, particularly those intended for drinking water.


Assuntos
Cladóceros/efeitos dos fármacos , Sedimentos Geológicos , Testes de Mutagenicidade/métodos , Zooplâncton/efeitos dos fármacos , Animais , Cladóceros/genética , Ecossistema , Ecotoxicologia/métodos , Água Doce , Testes para Micronúcleos/métodos , Tanques , Rios , Tunísia , Qualidade da Água
20.
Ecotoxicology ; 28(1): 62-68, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30594985

RESUMO

The use of indicator species to test for environmental stability and functioning is a widespread practice. In aquatic systems, several daphniids (Cladocera: Daphniidae) are commonly used as indicator species; registration of new pesticides are mandated by the Environmental Protection Agency to be accompanied by daphniid toxicity data. This reliance upon a few species to infer ecosystem health and function assumes similar responses to toxicants across species with potentially very different life histories and susceptibility. Incorporating lab-derived life-history data into a simple mathematical model, we explore the reliability of three different daphniid species as surrogates for each other by comparing their responses to reductions in survivorship and fecundity after simulated exposure to toxicants. Our results demonstrate that daphniid species' responses to toxicant exposure render them poor surrogates for one another, highlighting that caution should be exercised in using a surrogate approach to the use of indicator species in risk assessment.


Assuntos
Cladóceros/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Testes de Toxicidade , Animais , Traços de História de Vida , Modelos Biológicos , Especificidade da Espécie
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